Implant tools and techniques for implantation of a medical lead, catheter or other component are provided. The implant tools and techniques are particularly useful in implanting medical electrical leads in extravascular locations, including subcutaneous locations. An implant tool for implanting a medical lead may include a handle and a shaft adjacent the handle. The shaft has a proximal end, a distal end, and an open channel that extends from near the proximal end to the distal end, the open channel having a width that is greater than or equal to an outer diameter of the implantable medical lead.